2023 Volume 42 Issue 3 Pages 278-284
Synopsis: Malignant struma ovarii (MSO) is a rarely detected tumor, due to which its standard treatment has not been established.Key words: Malignant struma ovarii, intraperitoneal dissemination, peritoneal strumosis, radioactive iodine treatment, recurrence
We encountered a 39-year-old patient with MSO and intraperitoneal dissemination. At the age of 34 years, a histological examination of the left ovarian cyst during cesarean section revealed a struma ovarii. She was referred to our hospital because transvaginal ultrasound revealed a solid component within the ovarian cyst. Magnetic resonance imaging revealed a polycystic tumor with solid component within ovary. Blood test results demonstrated an elevated thyroglobulin level of 878 ng/mL; therefore, we suspected MSO. We performed a simple hysterectomy, bilateral salpingo-oophorectomy, omentectomy, and disseminated lesion resection. Surgery was performed without residual tumor. Histopathology revealed struma ovarii in the left ovary and papillary thyroid carcinoma in the right ovary, and struma ovarii in the omentum, surface of rectum, sigmoid mesentery, and ileal mesentery. After postoperative 1 year and 5 months, the patient was diagnosed with recurrent MSO using radioiodine scintigraphy and underwent thyroidectomy and radioactive iodine treatment. The recurrent tumor remarkably shrank after the treatment in computed tomography.
This study suggests that radioactive iodine may be useful in treating recurrent MSO and peritoneal strumosis.
